Japanese, Chinese, and Korean texts, as well as some other language texts, are rendered vertically instead of horizontally, as in Latin or Cyrillic texts and many other languages. In vertical text, characters are arranged in vertical lines, so that when a user reads the characters, the next character is either above or below the current character. Many documents and books containing such vertical text are increasingly in demand for eReaders.
Traditional optical character recognition and other eReader preparation software are typically designed for texts of Roman character schemes, which are horizontal. Scanning vertical texts for conversion to an eReader format can introduce errors because it is difficult to correctly align the page being scanned with sufficient accuracy to the horizontal and vertical axis of the scanner. Insufficient accuracy of scans can produce translation and rotation defects, skew, or character drift. For example, skew correction that provides accuracy within 1 in 100 may be insufficient for high quality electronic books.